目的:鉴于目前治疗绝经后骨质疏松症的抗再吸收药物的局限性,需要不损害骨吸收和骨形成之间的耦合串扰的替代方案。破骨细胞生成。葛根素,一种独特的C-糖苷异黄酮,被发现能够通过抑制骨吸收来防止骨丢失,但是潜在的机制是有争议的。在这项研究中,我们研究了葛根素对破骨细胞分化的影响,体外激活和骨吸收及其潜在的分子机制,然后用去卵巢(OVX)大鼠模型评价葛根素对骨代谢的影响。
方法:体外,葛根素对破骨细胞细胞毒性的影响,分化,凋亡,在原始264.7细胞和小鼠BMM中研究了激活和功能。通过RT-PCR确定破骨细胞相关标志物,westernblot,免疫荧光,和激酶活性测定。在体内,Micro-CT,组织学,血清骨生物标志物,采用力学试验评价葛根素预防骨质疏松的效果。
结果:葛根素显著抑制破骨细胞活化和骨吸收,不影响破骨细胞生成或凋亡。在机制方面,整合素β3蛋白的表达和Src的磷酸化,葛根素组Pyk2和Cbl低于对照组。口服葛根素可预防OVX诱导的小梁骨丢失,并显着提高大鼠的骨强度。此外,葛根素显著降低陷阱阳性破骨细胞数量和血清TRAP-5b,CTx1,不影响骨形成率。
结论:总的来说,葛根素通过抑制破骨细胞活化和骨吸收来预防OVX大鼠的骨丢失,通过抑制整合素-β3-Pyk2/Cbl/Src信号通路,不影响破骨细胞形成或凋亡。
UNASSIGNED:这些结果证明了葛根素对骨代谢的独特机制,并提供了预防绝经后骨质疏松症的新药物。
OBJECTIVE: Given the limitations of current anti-resorption agents for postmenopausal osteoporosis, there is a need for alternatives without impairing coupling crosstalk between bone resorption and bone formation ie. osteoclastogenesis. Puerarin, a unique C-glycoside isoflavonoid, was found to be able to prevent bone loss by inhibiting bone resorption, but the underlying mechanism was controversial. In this study, we investigated the effects of puerarin on osteoclastic differentiation, activation and bone resorption and its underlying molecular mechanism in vitro, and then evaluated the effects of puerarin on bone metabolism using an ovariectomized (OVX) rat model.
METHODS: In vitro, the effect of puerarin on osteoclastic cytotoxicity, differentiation, apoptosis, activation and function were studied in raw 264.7 cells and mouse BMMs. Mechanistically, osteoclast-related makers were determined by RT-PCR, western blot, immunofluorescence, and kinase activity assay. In vivo, Micro-CT, histology, serum bone biomarker, and mechanical testing were used to evaluate the effects of puerarin on preventing osteoporosis.
RESULTS: Puerarin significantly inhibited osteoclast activation and bone resorption, without affecting osteoclastogenesis or apoptosis. In terms of mechanism, the expressions of protein of integrin-β3 and phosphorylations of Src, Pyk2 and Cbl were lower in puerarin group than those in the control group. Oral administration of puerarin prevented OVX-induced trabecular bone loss and significantly improved bone strength in rats. Moreover, puerarin significantly decreased trap positive osteoclast numbers and serum TRAP-5b, CTx1, without affecting bone formation rate.
CONCLUSIONS: Collectively, puerarin prevented the bone loss in OVX rat through suppression of osteoclast activation and bone resorption, by inhibiting integrin-β3-Pyk2/Cbl/Src signaling pathway, without affecting osteoclasts formation or apoptosis.
UNASSIGNED: These results demonstrate the unique mechanism of puerarin on bone metabolism and provide a novel agent for prevention of postmenopausal osteoporosis.